Malicious PDF — malware analysis report

Static analysis result for SHA-256 b718d9c17a790b51…

MALICIOUS

PDF

86.6 KB Created: 2021-07-14 04:01:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ad48abf1d50e6d45aa64449c4bd36bab SHA-1: a402063a1e92b021eb4452c7cc5f102bf4b88bca SHA-256: b718d9c17a790b5128295043bd743e5e88bfaf372a5e706993a5a6079b4ea1e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting, suggesting a tactic to distribute or obscure malicious links. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malicious content distribution scheme, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.jobsincrete.gr/images/_user_na/file/sewasamaw.pdf
    • http://candientushinko.com/images/file/xagimabasujow.pdf
    • https://vntdc.com/upload/fck/file/5081982171.pdf
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1f6dc31af---dekuda.pdf
    • https://budapestpainter.hu/ckfinder/userfiles/files/kavuxotelotozowakuwa.pdf
    • http://gpn1971.org/clients/a/a2/a25689677492d603657f1241a2a69ea8/File/fixunisafu.pdf
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/b32ecea257173978eb50f6b299da0d2f/2635358442.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b918c37e67---wavufiwomaj.pdf
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/desakuvegotejigegeli.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160750e11c78a4---zizuwolarufologe.pdf
    • http://pgnsualumni.com/clients/872691/File/57035060634.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/5acb079293136ac37c2f77505fafaced/75025043062.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607410d5df702---xazawiwibaguweleda.pdf
    • http://vstarmp.cn/upload/files/20210710_142116.pdf
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/578ad337cb3d9a3efe8337a7cda962c7/semopovibadubuj.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/3lo03b1dn5o3oarr28amulls7b/sorabavoxabujaranixas.pdf
    • http://spc1991.com/ckfinder/userfiles/files/22881705272.pdf
    • http://veraschwemmle.de/fckdata/file/69892003419.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d86ada8e621---kadezuf.pdf
    • http://rheinmotel.com/userfiles/file/39059380427.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c3c1fb48d38---28285474013.pdf
    • http://fitsiluet.cz/data/file/15291373044.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609697fd2cd3e---27748319440.pdf
    • https://teyadegitimvideo.com/calisma2/files/uploads/nivejalorojananisikupogir.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=example+of+asexual+animals
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f015.bin
3eb69527226f983489688b8fa3783e3091f2afad94f31dcd711d009d638f37d7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF015 10504 bytes
font_01_sfnt_off000107ec.bin
4cd6133e6ec4eb8e63bd31bc5f7815df99095b97cbd3a44327f6a699a03961fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x107EC 17600 bytes
font_02_sfnt_off0001355e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1355E 16792 bytes